Deep well pump piston



Aug. 10, 1937. J. P. JACKSON DEEP WELL PUMP PISTON Filed Aug. 23, 1935 2 Sheets-Sheet 1 A TTORNEY Aug. 10, 1937. J; P. JACKSON DEEP WELL PUMP PISTON Filed Aug. 23, 1935 2 Sheets-Sheet 2 0/? 6 V \M aw JAMES PHILLlP'JACKSON.

INVENTOR A ORNEY Patented Aug. 10, 1937 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to deep well pumps and more particularly to pistons therefor.

An object of the present invention is to provide a piston for deep well pumps of the type disclosed 5 in my companion application, Serial Number 748,703, filed October 17, 1934, wherein the piston is employed both as a power piston and a pumping piston, and to provide such a piston which is composed of a plurality. of sections detachably 10 connected to hold piston cup leathers firmly and securely. in place and permit their ready replacement when their efiiciency becomes impaired from wear; and further to install the cup leathers with some of them cupping in one direction and 5 others in the opposite direction.

Another object of the present invention is to provide a piston as specified wherein all of the metallic parts of the piston are smaller in diameter than the cylinder in which it reciprocates,

20 thereby providing relatively large clearances between the pistcn body and cylinder wall, so that sand or other foreign matter will not cut or score the cylinder walls.

With these and other objects in view, as may 25 appear from the accompanying specification, the

invention consists of various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing a deep well pump piston of 30 the preferred form embodying the invention, and

the features forming the invention will be specifically pointed out in the claims.

In the drawings:

Figure 1 is a side elevation of the improved 5'piston.

Figure .2 is a longitudinal section through the piston with parts broken away.

Figure 3 is an end view of the piston.

Figure 4 is a cross-sectional view of the piston 40 taken on the line 44 of Figure 2.

Figure 5 is a cross-sectional view of the piston taken on the line 5-5 of Figure 2.

Figure 6 is a cross-sectional view taken on the line 6-6 of Figure 2.

45 Figure 7 is a side elevation of a modified form of the improved piston.

Figure 8 is a longitudinal sectional view through the modified form of the piston.

Figure 9 is a cross-sectional view taken on 50 the line 9-9 of Figure 8.

Figure 10 is a cross-section taken on the line Ill-I of Figure 8.

g Referring more particularly to the drawings, the improved piston which is particularly designed 55 for use in submerged deep well pumps such as disclosed in my companion application above referred to, comprises a carrying body I to which the piston rod 2 is detachably connected, such as by threaded connection shown at 3. The carrying body I has its inner or lower end shaped 6 to form one head, namely the power head 4 of the piston and it has an elongated extension formed thereon extending outwardly and upwardly from the annular shoulder 6. The extension 5 has a threaded stud 1 on its outer end on which the piston head 8 threads. The piston head 8 is held against accidental unthreading movement by the set screw 9.

A plurality of cup leathers ID are carried by the extension 5. While these members are referred to herein as cup leathers, it is to be understood that this term is employed because such elements in pump constructions are-commonly known as cup leathers. They may be constructed of any suitable material, with leather, rubber or any composition found practical without departing from the spirit of the present invention. The inner or lowermost cup leather Illa engages the shoulder 6 and is held tightly thereagainst by the spacer I la, while the intermediate cup leathers Hib are engaged by suitable combined supporting and spacing members I2. The upper or outermost cup leather Illc is held tightly against the spacer He by the inner cup engaging end M of the removable piston head 8. The combined supporting and spacing members l2 have substantially cylindrical portions l5 thereon which extend into the interior of the cupped portions of the cup leathers l0 and they have spacing and clamping heads I6 formed thereon which 86 engage against the outer surface of the bottoms of the cup leathers next thereto and clamp them against the ends of the portions l5 of the next combined supporting and spacing member in the piston assembly excepting only that the combined clamping and spacing portion Ila of the lower or innermost member l2 clamps the base of the cup leather Ilia against the shoulder 6. The diameter of the larger part of the substantially cylindrical portions I5 is smaller in diameter than the inner diameter of the cup leathers ID as clearly shown in Figure 2 of the drawings but each of the members I 2, the piston head 8 and the piston body I have annular abutment surfaces l'l formed thereon against which the inner surfaces of the cup leathers near the edges of the cups engage.

By particular reference to the drawings, it will be noted that the cup leather lllc cups towards the outer or upper end of the piston while the cup leather Ilia. cups towards the inner or lower 7 head 4 of the piston. The intermediate cup leathers l may all cup towards the head 4 or if it is so desired, a certain number of them in- 5 wardly from the head 4 may cup theretowards while the others cup towards the piston head 8. In pistons for deep well pumps of the type wherein the piston is used as both a power and a pumping piston it has been found highly practical to cup the cup leathers in opposed directions as just specified so as to insure efllcient pumping and relatively tight engagement between the piston and bore of the cylinder on both strokes of the piston.

Pumps of the type involved in the present invention are used for pumping crude petroleiun, water or other fluids from very deep wells and in the large majority of such pumping conditions sand or other foreign matter is at all times present in the fluid pumped. In the present invention the active portions of the piston are in reality the cup leathers, and all of the metallic parts of the piston are of a smaller diameterthan the bore of the cylinder 20, in which the piston reciprocates, (see Figure 1 of the drawings), thus providing a relatively great clearance between the metallic parts of the piston and the cylinder wall to prevent cutting or scoring of the cylinder. Also by making the piston with the metallic 3 parts smaller in diameter than the cylinder bore the wear occasioned by the reciprocation of the piston is taken up by the cup leathers I0. I These cup leathers are comparatively inexpensive and with the piston. constructed as shown in the drawings and hereinabove described, the leathers may be easily replaced when they have become worn sufliciently to'impair their eflicieirt pumping action.

As shown in Figure 2 of the drawings the 40 piston rod 2 extends a relatively great distance into the carrying body ofthe piston structure and the threaded portion 3 thereof is positioned inwardly from the lower open end of the bore 3a which receives the piston rod. The smooth or "unthreaded part or the piston rod 2 outwardly of the threaded part 3 is slightly smaller in diameter' than the bore 3w providing a very close clearance between the outer diameter of the piston rod and the bore which, together with the particular positioning of the screw threaded portion eliminates concentration of bending stresses at theroot of the thread during operation of the piston.

In Figures 7 to 10 inclusive a modified form oi! the improved piston is shown, which form is however similar in many respects to the form oi piston shown in Figures 1 to 6 inclusive.

In the modified form of the piston the carrying body 30 has an enlarged head 3i formed on its upper end which acts as the pumping head of the piston for pumping the fluid delivered by the pump. Between the piston head 3| and the carrying body 30 is an enlargementfl. which forms a spacer and guide for the uppermost cup leather.

if it is so desired without departing from the spirit of the present invention. The various cup leathers Illa, lb, and we ar held in their proper position on the carrying body 30 by combined supporting and spacing 6 members l5, while the two uppermost cup leathers are held in proper spaced relation by the spacing collar lie. The members I! in the modified construction of the piston are simila'rin con-' struction to the members I! oi. the preferred 10 form of the piston having end portions which clamp against the bases of the various cup leathers and flanges l6 which form spacers between the base of one cup leather and the edge.

of the other cup leather. The diameter of these 15 flanges or larger portions l3 and 01 the spacer llc as well as the piston head 3i are all smaller than the diameter of the bore of the cylinder in which the piston reciprocates, thus providing a relatively great clearance between the metallic 20 parts 01' the piston and the cylinder wall to pre-, vent cutting or scoring-of the cylinder.

The power head or end 33 of the piston of this modified form is formed of a separate piece and is detachably connected, such as by threaded con- 25 nection 34 with the lower end of'the carrying member 30 or with what might be called the reduced extension of the carrying member. The inner end of the member 33 is shaped similarly to the shape of the combined spacing and supporting members l5 and it formsa guiding support for the lowermost cup leather Ilia. The member 33 is threaded on the extensionor carrying body 30 and serves not only as the-power end P or head of the piston but as a clamping nut to 2 clamp the various cup. leathers I0, spacer I la and combined supports and spacers IS in proper position on the carrying body, to form the piston.

The carrying member 30 is provided with an tancethereto from its lower end and this bore. is threaded inwardly of its lower open end to receive the threaded portion 36 of the piston'rod I. As is clearly shown in Figure 2 of the drawings the f. threaded portion 33 of the piston rod is so located 5; that when the piston rod is properly connected 0 to the piston the threaded portion will be inwardly a considerable distance from theouter or lower open end oifthe bore 35 and the piston rod is slightly less in diameter than the diameter of 50 the bore so as to form the very close clearance between these members. The. construction oi the piston rod and its companion features on the carrying body eliminates concentration or bending stress at the root of the threaded portion 33. 5

. If it is so desired, set screws 31 and 38 may be provided for preventing accidental rotation of the piston rod and the member 33 respectively.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown but that they may be widely modified within the invention defined by carrying body having an axial bore therein extending into the body a distance greatly in excess oi. the diameter of the piston and having its inner end portion threaded, said piston rod provided with threads to engage in the threaded portion of said bore.

2. In a deep well pump piston, a carrying body having one end enlarged to form the pumping head of the piston, a plurality or cup leathers and spacers on said carrying body, and a member forming the. power head of the piston threaded on said carrying body and clamping said cup leathers and spacers in position, a piston rod, said carrying body having an axial bore therein extending into the body a distance greatly in excess of the diameter of the piston and having its inner end portion threaded, said piston rod provided with threads to engage in the threaded portion of said bore, said threaded portions being inwardly of the open end of the bore, said piston rod outwardly of its threaded portion being slightly smaller in diameter than the diameter of said bore.

3. In a deep well pump piston, a carrying body having an enlargement thereon forming one end of the piston, a piston head detachably carried by said carrying body, a plurality of cup leathers between said detachablehead and said enlargement, means carried byisaid carrying body holding said cup leathers in place, a piston rod, said carrying body having an axial bore therein extending into the body a distance greatly in excess of the diameter of the piston and having its inner end portion threaded, said piston rod provided with threads to engage in the threaded portion of said bore, said threaded portions being inwardly of the open end of the bore and said piston rod outwardly of its threaded portion being slightly smaller in diameter than the diameter of the bore.

4. In a deep well pump piston, a carrying body having one end enlarged to form one head of the piston, a. plurality of cup leathers and spacers on said body, a member forming the other head of the piston detachably connected to said body, a piston rod, said carrying body having an axial bore extending thereinto the inner end portion of which bore is threaded, said piston rod provided with threads to engage in the threaded portion of the bore.

5. In a deep well pump, piston, a carrying body having one end enlarged to form one head of the piston, a plurality of cup leathers on the body, a member forming theother head of the piston detachably connected to said body, cup leathers at the ends of the piston cupping outwardly towards the piston ends, said carrying body and said head-forming member having portions thereof extending into the end-most cup leathers and engaging portions of the inner surfaces of the cup leathers, a plurality of metallic spacers on said body for holding said cup leathers in proper spaced relation, the maximum diameter of said spacers and ofsaid head-forming member and the enlarged head-forming end of said carrying body being less than the maximum diameter of said cup leathers, a piston rod, said carrying body having an axial bore extending thereinto the inner end portion of which is threaded, said piston rod provided with threads to engage in the threaded portion of the bore.

6. In a deep well pump piston, a carrying body having one end enlarged to form one head of the piston, a plurality of cup leathers on the body, a member forming the other head of the piston detachably connected to said body, cup leathers at the ends of the piston cupping outwardly towards the piston ends, said carrying body and said head-forming member having portions thereof extending into the end-most cup leathers and engaging portions of the inner surfaces of the cup leathers, a plurality of metallic spacers on said body for holding said cup leathers in proper spaced relation, the maximum diameter of said spacers and of'said head-forming member and the enlarged head-forming end of said carrying body being less than the maximum diameter of said cup leathers, a piston rod, said carrying body having an axial bore extending thereinto the inner end portion of which is threaded, said piston rod provided with threads to engage in the threaded portion of the bore, the portion of said piston rod outwardly of its threaded portion being smaller in diameter than said axial bore.

7. Ir a piston for deep well pumps, a carrying body having its upper end enlarged to form a piston head integral with the carrying body, a piston head forming member detachably attached to the bottom or lower end of the carrying body, a plurality of cup leathers and spacers on the body intermediate said heads, said carrying body provided with a piston rod receiving bore extending upwardly thereinto, a piston rod extending into said bore and detachably connected to said body.

8. In a piston for deep well pumps, a carrying body having its upper end enlarged to form a piston head integral with the carrying body, a piston head forming member detachably-attached to the bottom or lower end of the carrying body, a plurality of cup leathers and spacers on the body intermediate said heads, said carrying body provided with a piston rod receiving bore extending upwardly thereinto, a piston rod extending into said bore and detachably connected to said body, the portion of said piston rod receiving bore near the end of the carrying body being larger in diameter than the diameter of the piston rod.

JAMES PHILLIP JACKSON. 

